import math

x1,y1,x2,y2 = map(float,input().split())

x_dis = abs(x1-x2)
y_dis = abs(y1-y2)

hypo = math.sqrt(x_dis**2 + y_dis**2)
dis = round(hypo,8)

print(dis) import math math x1,y1,x2,y2 = map(float,input().split()) x1 map(float,input().split()) map float input().split() ().split () input split y1 x2 y2 x_dis = abs(x1-x2) x_dis abs(x1-x2) abs x1-x2 x1 x2 y_dis = abs(y1-y2) y_dis abs(y1-y2) abs y1-y2 y1 y2 hypo = math.sqrt(x_dis**2 + y_dis**2) hypo math.sqrt(x_dis**2 + y_dis**2) math.sqrt math sqrt x_dis**2 + y_dis**2 x_dis**2 x_dis 2 y_dis**2 y_dis 2 dis = round(hypo,8) dis round(hypo,8) round hypo 8 print(dis) print dis hypo = math.sqrt(x_dis**2 + y_dis**2) math.sqrt(x_dis**2 + y_dis**2) hypo dis = round(hypo,8) round(hypo,8) dis y_dis = abs(y1-y2) abs(y1-y2) y_dis x2,y2 = map(float,input().split()) map(float,input().split()) x2 y1,x2,y2 = map(float,input().split()) map(float,input().split()) y1 y2 = map(float,input().split()) map(float,input().split()) y2 x1,y1,x2,y2 = map(float,input().split()) map(float,input().split()) x1 x_dis = abs(x1-x2) abs(x1-x2) x_dis
import math

x1,y1,x2,y2 = map(float,input().split())

x_dis = abs(x1-x2)
y_dis = abs(y1-y2)

hypo = math.sqrt(x_dis**2 + y_dis**2)
dis = round(hypo,8)

print(dis)
